DE1907360A1 - Process for the manufacture of expanded polystyrene bodies - Google Patents

Description

TOYO KAGAKU KABUSHIKI KAISHA, Kanagawa-Ken, Japan and DENKI KAGAKU KOGYO KABUSHIKI KAISHA, Tokyo-To, Japan

Process for the production of expanded polystyrene bodies

The invention relates to a method for producing moldings from closed-cell foams Extrusion and in particular the production of expanded polystyrene bodies made from uniform foam cells or -Droplets exist and have a smooth surface, sharp edges and a wood-like appearance and wood-like properties. have shafts.

So far, expanded polystyrenes are generally used, which are produced by extrusion and have densities that approximately correspond to specific weights between 0.10 and 0.15. The foams are extruded through nozzles, whose Access openings correspond to the cross-sectional areas of the shaped bodies, to be made from these foams. For this reason, it takes a lot of time and effort to design and manufacture the nozzles.

During the extrusion, the nozzles are cooled in an extreme manner in order to prevent the foamed material masses during

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extrusion through the nozzles due to internal gas pressure - swell. Therefore, the moldings can only with speed. can be produced that are far below the actual capacity of the injection molding machine, so that not only the capacity of the machines in each individual pail is strong is reduced, but also the mechanical life of the machines is much shorter.

In addition, when using such a method, it is not possible to give the molded bodies produced a good one To give surface gloss and sharp-edged corners, although this would be very desirable, and there is also no possibility of Manufacture injection molding compounds that lead to molded articles with the appearance and properties of wood, i.e. foam polystyrene articles to create with a specific weight between 0.2 and 0.8 *

The invention is therefore based on the object of a method for manufacturing while avoiding the disadvantages outlined of expanded polystyrene bodies with a smooth and shiny surface, sharp-edged corners, aesthetically pleasing appearance and to indicate properties similar to wood, which also makes it possible to choose these bodies in simple and complex Cross-sectional shapes such as those of foils, plates, rods, ducts. Create angles, polygons or rails, Furthermore, the foam material produced should be inexpensive and can be used instead of wood, as the wood processing due to the steadily decreasing wood stocks and the decreasing number of skilled workers is becoming more and more expensive. After all, the process is supposed to be easy and without expensive machines can be carried out and are also suitable for continuous and automatic operation.

The process for the production of molded bodies from expanded polystyrenes by kneading and gelatinizing one with a blowing agent

909850/142 *

medium mixed polystyrene mass in an extruder and by extrusion of this polystyrene mass in such a way that after the relaxation the foaming begins, this is to be solved Object according to the invention characterized in that the polyetyrene mass is extruded through at least one nozzle with a simply constructed opening, so that through it no irregularities arise in the stream of the polystyrene mass, which cause a Schaurapolyetyrorbildung that also the foams of f mass is pushed through a bounding window while the propellant is still decomposing within the polystyrene mass » and that the foam mass then cures immediately is cooled.

The foam polystyrene bodies produced by this process according to the invention have specific weights between 0.2 and 1.0, which correspond to the specific weights of wood.

The invention will now be described in detail with reference to the accompanying drawings, all of which are taken from the description and the details or features emerging from the figures can contribute to the solution of the object within the meaning of the invention and were included in the application with the intention of being patented.

The Pig. 1 is a perspective, partially sectioned view of a device for implementation of the method according to the invention.

The Pig. 2 shows one of the pig. 1 similar view of a

further embodiment of the invention.

The Pig. 3 and 4 are side views of other embodiments

games of the invention in which in a tubular nozzle a tubular mandrel is used.

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The Pig. 5 and 6 show in side and front views, respectively

Another embodiment of the invention, according to which the extruder nozzle from a Group consists of eight parallel nozzles. «

Fig. 7 is a section through a finished foam body, which after the hand of the Pig. and 6 described method is produced

According to the drawing, the polystyrene mass mixed with a blowing agent is fed to an extruder 1 and heated therein and kneaded until a molten or plasticized mass is formed. This mass is then extruded through a nozzle 2, which is simply constructed and has a shape such that it does not have irregularities in the flow the molten mass, while the foaming is suppressed so that only foam cores are formed what is due to internal pressure within the extruder. The foaming material is then stimulated to foam is extruded in such a way that when the pressure is removed, its maximum cross-sectional area is 6.5 times, preferably that is 2.5 to 6.5 times larger than the cross-sectional area of the nozzle opening.

The foam structures extruded in this way differ essentially differ from the foam structures formed by known processes, during the manufacture of which the Foam mass with a consistency of syrup or honey flows and drips and also differ from foam structures, which are almost like in normal injection molding processes are completely hardened when they flow out of the nozzle. The extruded in the manner described above Foam structures consist of a thermoplastic substance that contains gas bubbles and does not flow or drip, but a structure such as bread dough or plasticine

has a certain elasticity, which is caused by the so-called inner Gas pressure of the foam mass is conditional. For this reason "is the foam compound in a for production the most suitable and desirable state of lOrm bodies, i.e. in a state in which the molding work according to process en. Can be done as they are for clay work be applied.

However, the foam mass extruded in this way is then only reduced in cross-section when necessary subjected, the blowing agent still decomposing inside the foam and consequently the foam can swell due to the evolution of gas. Then the Foam compound forced through a boundary window 3, its opening - in cross section 1.5 to 6.5 times larger than that of the nozzle 2, wherein it is inflated by the internal gas pressure up to all corners of the boundary window 3.

Due to the above-mentioned requirements for accurate corner formation, a good surface gloss, a wood-like appearance and the properties of wood are, however Ratio between the opening areas of the nozzle and the: limiting window, i.e., the deformation ratio, 'imposes limitations. Results of experiments relating to This problem has been carried out are recorded in the following tables .1 and 2.

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Table 1

- \ Diameter (mm) gs- \
AreaX
(mm ² ) \ 2.5 1.0 3.0 1.0 3, Ui 6, 0 1.0 8th .D 10, 5 15th 1.0 30th 1.0 35 . : • 1V0 ·· ι \ Area (rom * =) 16 4.9 O 7.1 O 9, 6th 28, 3 50 , 2 86 5 176.6 706.5 961.6 see amount of
N. Propellants
N. (parts) 24 0.5 Δ · ¹ 0.5 O 0.5 1.0 0.5 0.5 1.0 0.5 1.0 0.5 0.5 0.5 Limit
window
size
'(mm) 35 O Δ O O O O Δ (O
O 4x4 70 O O O Δ O OO
w 4 X 6 105 O O O Δ O - ο 5x7 112. A. O O Δ - * 10 χ 7 140 A. O O O O A. 15 χ 7 150 Δ O O O O A. 14 x 8 170 O O O O O O Δ 20 χ 7 175 Δ O A. O O O O A. 25 χ 6 196 A. A. 0 O O O Δ 17 χ 10 O O O 0 Δ 25 χ 7 O O O 0 Δ 14 χ 14

<! O O <1 < O < < <l O <l O O O O
CM
H
O
•8th. O O G O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O <l < O O <l O O O < O < < < <1 <l <3 < < < < O O O • O < U.N.
CM he"
K
U.N.
KN C-
H
in
KN I 30 χ 15 I. 450 I 42 χ 12 I 504 O
U.N.
KN
O
K
in
KN CM
KN
CM
H
VO
KN 462 I 45 χ 11 j 495 O
O
U.N.
O
CM
U.N.
CM C-
V
U.N.
X
C- j 42 χ 11 xJ I 150 χ 10! 1500 | ____ 225O
4000 K j 150 χ 15

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- 8 Table 2

\ Jet
V diameter (ram) 18th 2 VJl 3 0.5 0 3 0.5 • 5 6th 0 \ Area (mm) 26th 4, 9 7, O 1 9 O 6th 28, 3 '■■ Amount of
Propellant
(Parts) 37.5 0.5 1.0 O 1.0 O 1.0 0.5 1.0 Top χ bottom \
side χ height \
AreaX
2 \
(mm) (mm) \ 73.5 O O O O O O 4 x 5x4 114.75 O O O O Δ 6 χ 7x4 O O Δ 7x8 χ 5 Δ O O 9x12x7 A. C. O 1? χ 15 χ 8.5

pie results above show the design limits involved in making an object with a trapezoidal shape Cross-section from a circular nozzle of the nozzle exit surface by the deformation "dependent on the boundary window" relationship are imposed.

Pas symbol O

Pas symbol

means accurate corner formation _#

means accurate but unstable cornering.

Pieces left blank mean operating conditions under which accurate corner formation cannot be obtained.

From the results of Tables 1 and 2 it follows that for the limit enzungB window 3 a cross-section β flat is desired that

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1.5 to 6.5 times as large as the cross-sectional area of the nozzle opening is. If such a ratio is chosen, then the foam is expanded by the gas pressure "or widened and into all corners of the boundary window 3 spread. The foam is then placed in a cooling bath 4 and cured.

The term "polystyrene" is understood here, in addition to polystyrene homopolymers, to mean all plastic materials which result from the copolymerization of monomers such as acrylonitrile and butadiene with styrene, such as acrylonitrile styrene (AS ^ copolymers, acrylonitrile-butadiene styrene copolymers and impact-resistant polystyrene compounds.

As a blowing agent used in the extrusion of expanded polystyrene fabrics Suitable include hydrocarbon gases, which are used for high-foaming molding, and solid blowing agents called, which are used for moldings made of materials such as rubber and polyvinyl chlorides.

Solid propellants are preferred for the purposes of the invention because they are easy to handle in the storage and ^one forming. Examples of particularly suitable propellants are azodicarbonamide, toluenesulfohydrazide, benzene-1,3-disulfohydrazide, diphenyloxy-4,4'-disulfohydrazide, Ιί, Ιί'-rdinitrosopentamethylene tetramine ,. Mtrourea and tert-butylamine nitryl. ■ ^; -

TJm to make the foam globules or bubbles uniform and the result is a smooth surface, auxiliary blowing agents can also be used. Examples of such Auxiliary propellants are oxalic acid, citric acid, guanidine carbonate, anhydrous potassium carbonate, zinc chloride, succinic acid, Lactic acid, orthophosphoric acid, borax, cadmium oxide, zinc dust, barium stearate, magnesium oxide, aluminum stearate, Calcium carbonate, lead acetate, zinc oxide, calcium stearate, aluminum oxide, Urea stearate and zinc laurate.

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Because of the special mode of operation in which the foaming • in the extruder 1 and in the! Nozzle 2 for the formation of show germs limited, but free foaming is permitted when the plastic compound has emerged from the nozzle 2 the preferred temperatures of the extruder barrel and the nozzle in the following ranges.

Cylinder temperature: O ₁ 150 to 230 ⁰ O

.C ₂ 120 to 180 ° 0

Nozzle temperature: D ₁ 110 to 135 ⁰ C

D ₂ 115 to 160 ⁰ C D ₃ 125 to 170 ⁰ C

Regardless of the shape of the expanded polystyrene body (square, rectangular, triangular or in the case of a rail irregular) in each case the opening of the nozzle 2 becomes a Form given that no irregularities in the flow of the melted Resin mass and which, in order to simplify the manufacture of the nozzle, is of simple construction, examples for such simple shapes of the nozzle opening circular, elliptical and cylindrical nozzle openings, where the latter is used to manufacture both hollow and solid bodies.

According to the invention, the foam mass extruded through the nozzle 2 can be used are fed directly to the boundary window 3 as described above. Shall be an object with irregular Cross-section are produced, which differs significantly from that of the nozzle opening (Fig. 1 and 4), then can the foam race first with the help of forming rollers 5 are preformed, the profile of the cross-sectional area of the is adapted to the object to be produced. As a result, the foam mass enters or passes through it facilitated by the boundary window 3, and its shape se ig ens are improved.

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The efficiency of the above-mentioned forming rollers 5 for improved shaping of the foam masses is shown in the following example. 100 parts of a polystyrene which 0.5 parts Azodicarbonaroid are added are melted, kneaded and extruded by an extruder 1, the successively provided with circular nozzle 2 with different opening cross sections and at a cylinder temperature of 190 ⁰ C and a Düsenteroperatur 125 ⁰ C is operated.

The in this way extruded show fabric mass is with Preformed with the help of forming rollers 5 and then through square delimitation windows 3 of different sizes printed to make square rods used for appraisal The efficiency of the forming rollers 5 can be examined. The results of these experiments are in Table 3 below.

Limit
(mm Tabel 3 Formation
roll
Efficiency 4 χ X Nozzle size
(mm) 5 x window Deformation
relationship
(GS / DS) X 2.5 15 χ 4th 2.03 X 3.5 30 χ ■ 7 3.18 X 6.0 , 35 x 7th 5.57 X 8.0 150 χ 7th 8.35 O 10, .5 200 χ 10 10.61 O 30.0 10 15.92 35.0 20th 36.39

The symbol X means: ineffective. The symbol O means »effective.

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From the results of Table 3 it appears that when injection molding from a nozzle 2 with a large cross-section, the Foaming behavior on the surface and inside the molten mass in the area of the nozzle opening is different and the inner part foams more so that excess propellant gas that is generated inside collects. and breaking through the outer surface of the molten resin.

As can also be seen from Table 3, the internal propellant gas in the case of a molded body is released after extrusion is greatly deformed by the boundary window 3 by the strong pressure accompanying the deformation pressed through the surface. Accordingly, it is extremely difficult to at Using only a bounding window with an object to obtain a smooth surface and sharp edges.

In contrast to this, by applying the invention it is possible Foam polystyrene body with a smooth surface, sharp edges, a fine, wood-like grain and also to produce other properties similar to wood, even if nozzles with a large diameter are used and with high deformation ratio is worked, namely on Reason for sizing after shaping. This is because of this achieves that the excess propellant is drawn off by inserting a tubular mandrel into a round nozzle end used and the foam mass thereby over a torpedo to be led.

The excess propellant gas is removed in the following way, pulled (see. Fig. 3 and 4). The olystyrene mass mixed with a blowing agent is fed to the extruder and heated and kneaded until it is in a liquid state. Then when the foaming of the molten mass through the inner Pressure is suppressed, the mass is replaced by a tubular

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ge nozzle 2 extruded, the annular opening through the Inner wall of the nozzle body and the outer wall of a tubular mandrel 7 is formed. Through the middle of the cathedral 7 leads a gas discharge line 6, which leads through the extruder 1, is arranged koaxial.in the nozzle 2, via the outlet opening the nozzle protrudes and on the other side with the tree surrounding the injection molding machine in connection stands. The nozzle 2 is also of a simple shape so that it does not have any irregularities in the flow of molten foam mass caused.

When the foam mass is extruded in this way and exiting the die, it will be different from that in the extruder pressure exerted on them and therefore foams in such a way that their cross-sectional area expands to a maximum value, which is equal to 6.5 times the cross-sectional area of the The outlet opening of the nozzle 2 is. The foam will mass off extruded in this way into a tubular hose. Subsequently, this is done while he is still in a state is located in which the propellant contained in it decomposes and expands, optionally subject to a reduction in cross section or not, and the excess Propellant gas within this tubular structure is, for example, through the gas outflow opening 6 of the mandrel 7 expelled by squeezing the hose. '■

The downstream end of the tubular foam · fabric structure is then pressed through a delimitation window 3, where the mass is inflated by the internal gas pressure up to all corners of the boundary window .. The · on this Way sized foam body is made then passed into a cooling bath 4, where it is cooled and hardened.

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In cases where the sizes and / or shapes of the nozzle opening or the cross section of the desired molded body The foam race can be preformed by means of forroating rollers 5 as described above which greatly simplifies the shaping to the final shape.

Because of the above-described construction of the extruder 1 and the nozzle 2, through which the excess blowing agent from the inside of the extruded mass is conveyed to a place outside the machine, the excess can, when Compression of the foam mass produced blowing agent be discharged even if the hollow foam tube after the extrusion between the forming rollers or in the boundary window 3 excessively strong squeezed will.

For this reason, regardless of the size of the deformation ratio, the surface of the product is always smooth, and sharp edges are obtained.

In Table 4, test results are given which make it clear what influence the removal of the excess Propellant has on the molding.

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- 15 Table 4

70 10.5 12th 15th 2C ) 2 30th 40 46 64 ■!
98 105 6th 6th 8th 15th ) 1 22nd 32 38 56 90 112 58 85 126 137 20th 327 452
> 528 754 1181 140 O O • 150 O O O O 170 O O O O 175 O O O O O WJXisen-
^ vVvd ur chm ess er
\ Jv \ (mm) 196 O O O O O ^ Do r n-
Be _ \ diameter
eren \ ( ^mra ). "210 O O O O O charging \ discharging
window opening
( ^mm ) \ (mm ² ) 245 O O O O O 10 χ 7 315 O O O O O 15 χ 7 385 O O O O O Δ 14 χ 8 432 O O O O O O - 20 χ 7 450 O O O O O O A. 25 χ 6 462 O O O O O O O A. 17 χ 10 495 Δ O O O C. O O O 25 x 7 500 O O O O O O O 14 X 14 504 O O O O O O O 50 χ 7 517 O O O O O C. O 55 χ 7 1200 - O O O O O C. O 55 χ 9 1500 O O O O O O O 55 χ 11 1800 O O O O O O O Δ 5ö x 12 2250 O O O O O O 50 χ 15 4000 O O O O O 12 χ 11 O O O O O A5 χ 11 A. O O G O 25 x 20 O O 42 χ 12 47 x 11 100 χ 1-2 150 χ 10 150 χ 12 150 χ 15 200 χ 20

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The symbol O indicates sharp edges.

The symbol Δ indicates sharp, but not stable, edge formation at.

D3.e spaces indicate conditions under which a sharp Skill formation cannot be obtained.

Plastic masses which are extruded from a nozzle 2 with a large opening or are severely deformed in the boundary window 3, are preformed with the aid of Forroierungsrollen 5 or shaped in that by means of a mandrel 7 and one in this located gas discharge line 6 gas is withdrawn.

However, in order to be able to produce moldings according to the invention, the surfaces of which are similar to wood and have a strong shine, the melted foam is passed through a nozzle with a simple opening shape, for example a circle or a Ellipse, extruded, so that there are no irregularities or irregularities in the flow of the plastic compound know, no matter how the cross-sectional shape of the end pro-αμ ^ ββ is. For this reason, in the case of custom-made products, the cross-sectional shape is essentially different from that mentioned above simple opening shape, the deformation ratio, never inevitable due to the requirement mentioned above, according to the invention to achieve the desired effect is limited.

Ep has shown that this disadvantage can be overcome by the fact that the outlet opening of the simply constructed Divides nozzle into several outlet openings.

For this purpose, more complicated shaped bodies are used in the manufacture According to a further embodiment of the invention the shape of the desired shaped body, e.g. a channel, an angle or a polygon, at least two

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above-mentioned breasts of simple shape are used, as in the Pig, 5 through 7 is shown. The foam masses extruded in this way melt as the foaming process progresses and then form a uniform structure with a shape approximating that of the desired molded article. Then this structure is through the boundary window 3 printed in a state in which the propellant is expanding within the Mass still decomposed. The gas pressure within the molten foam mass inevitably expands it into all corners of the limit window 3. The molded body produced in this way is then immediately passed into a cooling bath 4, cooled and hardened et.

As mentioned above, the invention provides a method for Manufacture of expanded polystyrene bodies, a polystyrene mass mixed with a blowing agent being kneaded in the extruder 1 and gelatinized and then passed through one or more nozzles 2 of simple shape that do not have irregularities in the flow of the Effect plastic mass, is extruded. The foaming of the foam mass within the extruder 1 is included limited to the mere formation of foam cores so that free peeling is possible after relaxation. the Foam compound is expanded by this foaming to a cross-sectional area that is 6.5 times, preferably the 2.5-. up to 6.5 times the opening area of the nozzle and then after extrusion with or without a previous cross-section It is reduced as long as it is still in a state in which the propellant is decomposing through a limiting window 3 pressed, the cross-sectional area of which is about 1.5 to 6.5 times as large as the opening area of the nozzle. The internal gas pressure forces the foam to expand into all corners of the delimitation fuse.

In the case of extrusion through nozzles with a large cross-section

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or in the case of an extrusion with a large deformation ratio .At the boundary window 3 after, the extrusion becomes the molten Show material mass from a nozzle 2 with such a simple construction that there are no irregularities in the flow. ben, extruded in the form of a hollow body. The nozzle points it has a cylindrical shape and has in its interior a tubular mandrel 7, which emerges from the outlet opening of the Düae 2 protrudes and a gas outlet opening 6 in the middle has, extends through the nozzle and the extruder 1 and communicates with an area outside the extruder stands. The plastic extruded in this way is squeezed between the forming rollers 5 or constricted in the delimitation window 3 and thereby in a solid state brought. The resulting excess blowing agent is withdrawn from the inside of the extruder. According to a Another embodiment, the foam mass can also through an arrangement of parallel nozzles 2 corresponding to the shape of the desired object can be extruded. The bloating the foam masses extruded on the latter method is used to fuse the parts flowing out of the individual nozzles into a single structure and thereby producing a body whose shape approximates that of the desired article. This will be Avoid harmful influences that would otherwise result from deformation.

Another feature of the invention is that mass production of display polystyrene bodies is made possible, without decreasing the efficiency of the injection molding machines, since the molten foam mass extrudes under conditions which allow free flow through one or more nozzles of simple construction.

Another essential advantage of the invention is that the specific weights of the finished molded body are free

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selectable within a range between 0.2 and 0.8, which is similar to that of wood, and that the finished moldings "Particularly 'desirable properties such as sharp edges, smooth surfaces with high gloss and the appearance and the Have the texture of wood or wood products.

In the following some special embodiments are given, however, to which the invention is not limited.

example 1

A mixture, which is prepared by adding 0.5 parts of azodicarbonamide to 100 parts of a polystyrene (melt index MI = 0.58), is _{kneaded in an extruder at a cylinder temperature C 1} of 181 ⁰ G and through a circular nozzle with a Diameter of 3.5 mm at a temperature D ₁ of 129 ⁰ C extruded. The foam produced in this way, while it is in a state in which the propellant is still decomposing and expanding, is forced through a boundary window with a trapezoidal cross-section, the upper side 4 mm, the lower side 5 mm and the height thereof 4 rom amounts. Then it is cooled and hardened.

The finished molded body consists of expanded polystyrene with a specific weight of 0.41 and has neat corners, a smooth surface of high gloss and the appearance and grain of processed wood.

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Bend ■ Longitudinal direction
(Span 200 mm) Flexural strength
(kg / cm) 20 io (kg / mm ² ) ' Surface direction
(kg / cm) example
1 1.1 - wood
(Cedar) characteristic Width direction
(Span 30 ram) Bend (mm) 40. # (kg / ram ² ) Side direction
(kg / cm) 243 2.8 110-665 Compression B e strength
(kg / cm ² ) I hardness' (kg / mm) 14th 0.5 10 Bend (totd) Bending impact 2
attempt (kg-cm / cm) 4.2 34 specific weight _ 0.41 1 Ifagel-
qugkraft 0.3-0.4 0.5-0.7 0.5-0.8 19.6 0.3-0.4 8th 12th

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Example 2

Mixture, which is produced by adding one part of azodicarbonamide 1DO parts of polystyrene (GP: HI = 7: 3, MI = 0.65), is _{kneaded in an extruder at a cylinder temperature G 1} of 210 ^° C. and through a circular nozzle a diameter of 64 mm at a temperature D ₁ of 120 0 extruded. The resulting foam mass is preformed with rectangular forming rollers and, while it is in a state in which the propellant is still decomposing and expanding, is pressed through a rectangular boundary window which is 150 χ 15 mm in size. The foam is then cooled and hardened.

lis results in a rod with a rectangular cross-section made of expanded polystyrene, which has a specific gravity of 0.5, accurate corners and a wood-like appearance with high gloss.

By adding HI to this foam compound A hard, tough material is created.

characteristic Bend Longitudinal direction Kampression 20 ^c / o (kg / mm ² ) Flexural strength
(kg / cm ² ) Hard e (kg / msr) specific weight Surface direction
(kg / cm) example
2 wood
(Cedar) (Span 200 mm) 40 ^c / o (kg / ram ^) Bend (mm) Flexural impact
.trial (kg-cm / cn nail S e rtion
(kg / cm) 156 110-665 Width direction
(Span 30 mm) Flexural strength
ρ
(kff / cm) ι) traction
Λ 28 10 Bend (mm) 140 34 - 3 1 1.5 0.3-0.4 3.6 0.5-0.7 0.47 0.5-0.8 6.2 19.6 0.50 0.3-0.4 20th 8th 28 12th

50 / \ 42T

Example 3

A mixture of 0.5 parts Azodicarbonaraid and 100 parts of a polystyrene (MI = 0.58) was kneaded in an extruder at a cylinder temperature of 190 C. ⁰ O UNU then in a tubular shape by a tubular nozzle with an Öffnungsdurchraesser of

2 20 mm and an outlet opening of 137 mm extruded. The.

The nozzle is provided with a mandrel, the bore of which is 15 mm, which protrudes from the outlet tip of the nozzle and which has a central gas outlet opening which is in connection with an area outside the extruder. The nozzle is at a temperature D of 120 ⁰ C.

The foam mass in the form of a pipe is, while it is in a state in which the propellant is still decomposed and, by constricting it, passed through a dimensioning window with a size of 35 x 7 mm. At-*- This is followed by cooling and hardening. . "...-.

A polystyrene mass is obtained with a lower degree of Foaming, a specific gravity of 0.42, smooth surface, precise, sharp edges and a wood-grained appearance.

characteristic Bend Longitudinal direction
(Span width e 20 0 rnm) Flexural strength -
. (icg / en ² )
Bend (rnm) 20 <& Cfer / mm ² } Surface direction
(kg / cm) example
3 HaIz:
(Cedar) Width direction
(Span 30 mm) Flexural strength
(kg / cm2).
Bend (mm) 40 ° / o (kg / mm ^ ( S e rtion
(kg / cm) 240 110-665 compression Hardness (kg / nra ² ) 14th 10- r väfuof ¹ ^ "te - =.» / - ² ) 220 . , 34, specific weight 1 1 f N% gel ~
Zi ^ g strength .1,1 .... 0.3-0.4 f 2.8 0.5-0.7 0.5 0.5-0 _r 8 4.2 19.6: 0.42 0.3-0 »4 15th 8th 23 t2
H

BATH ORIGINAL

Example 4

ijline by the addition of 1.0 parts of azodicarbonamide to 100 parts of a polystyrene-kneaded mixture Vird prepared in an extruder at a cylinder temperature of 200 C. ⁰ C (GH 3, MI = O, 65: 1 n = 7). The cash register obtained is in the form of a tube through a tubular nozzle with a bore diameter of 15 mm

'2

It is extruded from an exit area of 126 mm, the nozzle having a mandrel with a bore diameter of 8 mm and a central gas reference opening which is in communication with an area outside the extruder and protrudes from the exit opening of the nozzle Nozzle temperature D- is 120 ⁰ C. '

while it is in a state in which the propellant is still replaced and after it has been constricted, it is pressed and preformed by means of forming rollers and then printed through a rectangular window with a size of 25 x 20 mm The excess blowing agent is drawn off from the interior of the parzma3se through the gas discharge opening in the mandrel into the space outside the extruder. The finished body is cooled and hardened.

Jfein receives a rod-shaped polystyrene body with a low degree of Schäuraung and a specific weight of 0.43. Its surface is smooth, it has sharp edges, it is tough and has a wood-like appearance.

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characteristic Bend Longitudinal direction
(Span 200 mm) Flexural strength
(kg / cm ² ) Surface direction
(kg / cm) example
4th wood
(Cedar) Width direction
Span 30 rom) Bend (mm) Side direction ■;
(kg / cm) 160 110-665 Kpmpression Flexural strength
(kg / cm ² ) 28 10 Bend (mm) 142 34 20 io (kg / mm ² ) 3 1 40 ° /> (kg / mm ^) VO .0.3-0.4 Hardness (kg / mm ² ) 2.5 0.5-0.7 0.4 0.5-0.8 specific weight 5.3 19.6 Ifpge 1-
traction 0.43 0.3-0.4 15th 8th 23 12th

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Example 5

E-.ne mixture of 0.5 parts and 100 parts Azodicarbonaroid e., Nes polystyrene (MI = 0.5B) is kneaded in an extruder at a Zvlindertemperatur C ₁ of 180 ⁰ C and by a group of five parallel arranged nozzles a circular shaped opening of 3.5 mm diameter at a nozzle temperature D ₁ of 130 ⁰ C extruded. The masses extruded through the five nozzles are fused into a unitary, coherent foam mass which, while it is in a state in which the propellant decomposes and the mass expands, through a rectangular window with a width of 42 mm and at a height of 7 km. The mass is then cooled and hardened.

Mun receives a foam polystyrene plate with a low Gyad of foaming, which has a specific gravity of 0.47, sharp edges, a smooth surface with a high gloss and that Has the appearance of processed wood.

ι ■ ■■
characteristic Longitudinal direction
(Span 200 mm) Flexural strength
(kg / cm) Surface direction
(kg / cm) example
5 wood
(Cedar) Bend Width direction
(Span 30 mm) Bend (mm) Side direction
(lcg / cro) 236 110-665 compression Flexural strength
(te / cm) 14th 10 Bend (mm) .210 34 20 io (kg / mm ² ) 1 1 40 ° / ° (kg / mm ^) 1.1. 0.3-0.4 Hardness - (kg / mm) 2.8 0.5-0.7 ^ f ^ ^hlag - (kg-oa / c ² ) 0.5 0.5-0.8 specific weight 4.2 ' 19.6 Na ^ eI- 0.43 0.3-0.4 traction 15th 8th 23 12th

909850 / U27

3e! Game 6

jJine by adding one part Azodicarbonaraid to 100 parts of a polystyrene (GP: HI = 7: 3, MI = 0.65) Miychung prepared is kneaded in an extruder at a cylinder temperature of 185 C ₁ ⁰ G and oh by a group of! ; U-shaped and nozzles arranged parallel to one another (cf. I ¹ Ig. 5 and 6). Each nozzle is circular, has a diameter of 30 mm and is equipped with a mandrel 7a of 8 mm diameter, which has a central gas discharge opening 6a. The die temperature D ^ is 115 ⁰ C

There are eight foam streams fused to form a coherent foam structure, which is then ! ■ ollen preformed and while it is still in one state is located in which the propellant decomposes and the ! let expanded, through a bounding window with a U-shaped or channel-shaped cross-section, the width of which is 150 mm, whose height is 110 mm and whose wall thickness is 1 mm (cf. Pig. 7). The foam mass is then cooled and cured.

Έβ results in a polystyrene foam body with a low degree of ap. Foam and a specific weight of 0.49, the sharp edges and a wood-like appearance with a smooth upper and high gloss.

909850/1427

characteristic Ügung Longitudinal direction
(Span 200 mm) Flexural strength
(kg / cm ² ). compression 20 $ (kr- / r.ra ² ) Surface direction (kg / cm) example
6th wood
(Cedar) Width direction
(Span 30 ram) Bend (τητα) 40 ^c / o (kg / mm) Side direction (kg / cm) 140 110-665 Flexural strength
(kg / cm ² ) Hardness (kg / mm ² ) 28 '10 • bend (mm) Flexural impact (kc-cn / cm ² )
trial- ^ ^{s CII1} / ^cm > 136 34 specific weight 3 1 tfagel- 1.3 0.3-0.4 traction 3.2 0.5-0.7 0.52 0.5-0.8 5.9 19.6 0.49 0.3-0.4 '18 8th 25th 12th

909850/1427

Claims (6)

Claims Process for the production of molded articles from foam poly- £, tyrolize by kneading and gelatinizing one with a propellant mixed polystyrene rugs in an extruder and through c. such extrusion of this polystyrene mass that foaming begins after the relaxation, thereby characterized in that the polystyrene mass extruded through at least one Düae with a simply constructed opening so that through them there are no irregularities in the flow qer polystyrene mass arise, which a Schauropolystyrolbilqung cause that further the foam mass is pressed through a window (3), while the propellant still decomposes within the polystyrene mass, and that the foam mass is then immediately cooled to harden. 2. The method according to claim 1, dadurchge ken n characterized in that the polystyrene mass is left to the Schäuroung at most until its cross-sectional area is 6.5 times as large as that of the nozzle opening that this. Foam compound is then pre-formed if necessary and then printed through a delimitation window, the cross-section of which is 1.5 to 6.5 times as large as that of the nozzle opening. ^: .: -. ■■ - ·; : ... 3. The method according to claim 1 or 2, since d u r ch \ characterized in that for the production of a tubular shaped body, the nozzle (s) has a hollow cylindrical Pprm and has a mandrel (7) in its interior (en) that protrudes from the nozzle outlet opening and is provided with a gas outlet opening (6a) in its center, those with an area outside the extruder in terms of flow communicates and removes excess, within of extruded, tubular or tubular foams The propellant formed is used when the foam is pressed darch the boundary window. 90985Ό / 1427 4. The method according to one of claims 1 to 3, characterized in that for extrusion of the polystyrene mass at least two nozzles arranged in parallel are used, so that during the extrusion at least two foam structures are created, which then become a cohesive one Forms are fused and then pushed through the limit window. ?. Method according to one of Claims 1 to 4, characterized in that the method is carried out continuously and automatically. 5. The method according to any one of claims 1 to 5, characterized in that the cylinder ^{temperature of the extruder is about 120 to 230 0} O and the temperature of the nozzle or nozzles is about 110 to 170 ⁰ C. '/. Method according to one of Claims 1 to 6, tia marked by the fact that the extrusion " in such a way that the expanded polystyrene after extrusion is comparable to that of bread dough or plasticine Has consistency. 6. Schaurapolystyrene body, produced according to the process ^ iach one or more of claims 1 to 7, characterized in that it has a specific gravity of 0.2 to 1.0. 909850 / U27